The present invention is directed to communications systems and, more particularly, to methods and apparatus for providing call retry and/or call waiting services.
Calls to busy telephone numbers are normally not billed. Accordingly, from the telephone company perspective, calls to busy telephone numbers represent an unprofitable and therefore undesirable service which they are required to provide. From the telephone company""s perspective, increased rates of successful call completion can have a direct impact on profitability.
From a calling party""s perspective uncompleted calls to busy telephone numbers are also undesirable since the call must be repeated if the calling party is to ultimately reach the called party. In order to help a calling party, some private branch exchange (PBX) equipment has been implemented which includes an automatic repeat call feature. This feature allows a calling party to have the PBX repeatedly place a call to a telephone number entered by the calling party, at periodic intervals, until the called line is no longer busy and the call is answered.
While such repeated automated dialing can be useful to the calling party, such an approach to a call retry service requires special hardware at the caller""s premises. In addition the PBX based call retry service has the disadvantage of producing numerous calls which must be handled by the public telephone network but which can not be billed for since they are not successfully completed to the called party""s line.
Various premium services, e.g., call waiting services, have been offered to telephone service subscriber""s to allow them to interrupt an ongoing call and accept a call. This allows at least some calls, which would otherwise not be completed due to a busy line condition, to be completed successfully.
With call waiting services, the telephone switch which services the called party usually generates a call waiting tone in response to an incoming call directed to a busy line with call waiting service. In response to the call waiting tone, the called party can put the existing call on hold by performing a hook flash operation, i.e., briefly depressing and then releasing the phone hook. In response to this hook flash, the calling party is connected to the called party while the previous caller is placed on hold.
In order to give the called party the opportunity to make an educated decision as to whether or not to interrupt an ongoing call for an incoming call, in one premium call waiting service known as Talking Call Waiting, an audio version of the name of the calling party is played to the called party after the call waiting tone. The name played to the called party is obtained using ANI techniques.
Unfortunately existing call waiting services are limited to providing the called party the opportunity to take or reject a call while on an existing call. It would be nice if the called party, e.g., the call waiting service subscriber, could have a larger range of call disposition options, e.g., it would be desirable for the called party to have the option of asking the calling party to wait until the existing call is completed or to send the incoming call to a voice mail system, e.g., answering machine.
Significantly, there is currently no network based way to have a calling party wait for an extended period of time for a called party to hang up, and then have the calling party automatically connected to the called party.
In order to provide enhanced telephone services, many telephone companies now implement a telephone communications network as an Advanced Intelligent Network (AIN) which has made it easier to provide a wide array of previously unavailable telephone services. In an AIN system, telephone central offices each include one or more switches, each of which serves as a signal switching point (SSP). Each SSP can detect one of a number of call processing events identified as AIN xe2x80x9ctriggersxe2x80x9d or events. An SSP which detects a trigger suspends processing of the call which activated the trigger, compiles a call data message and forwards that message via a common channel interoffice signaling (CCIS), utilizing the Signal System 7(SS-7) protocol, link to a database system, such as a Service Control Point (SCP). The SCP may be implemented as part of an integrated service control point (ISCP). If needed, the SCP can instruct the central office SSP at which the AIN trigger was activated to obtain and forward additional information, e.g., information relating to the call. For example, AIN supports a Monitor_for_Change message which can be sent to an SSP. In response to the Monitor_for Change message, the SSP checks on the status of the line associated with the message and reports that line status back to the SCP.
The SCP accesses stored call processing information or records (CPRs) to generate from the data received from the SSP one or more control messages. The call control messages are used to instruct the central office on how to process the call which activated the AIN trigger. As part of the call control message, an ISCP can instruct the central office to send the call to an outside resource, such as an intelligent peripheral (IP) using a send to outside resource (STOR) instruction. IPs are frequently coupled to SSPs to provide message announcement capabilities, voice recognition capabilities and other functionality which is not normally provided by the central office. Control messages are normally communicated from the SCP to the SSP handling the call via a CCIS/SS-7 link. The SSP will complete the call which originally activated the AIN trigger in accordance with the instructions received in the control message received from the SCP.
Given that telephone companies have made significant investments in implementing AIN, they are constantly looking for new services, which can be offered using AIN capabilities, e.g., services for which they can charge customers or which reduce the costs associated with servicing existing customers.
To facilitate telephone system and computer system interaction, a TAPI (telephone application programming interface) has begun to be supported by Microsoft Corporation and other computer software providers. TAPI is intended for use by computer systems and other electronic devices which are coupled to a telephone device thereby allowing the attached electronic device and/or computer to receive signals communicated over a telephone line and to send signals from the attached device and/or computer to the attached telephone device. TAPI signaling can be used to communicate text information to a TAPI device, e.g., during an ongoing telephone call.
In view of the above discussion, it should be apparent that it would be desirable if the telephone network could offer a network based, as opposed to customer premise, e.g., PBX, based call retry service. Improved call waiting services which offer a called party multiple call disposition options are also desirable. The combination of a call waiting service with a call retry service whereby a caller to a busy line could be asked to hold while the called party completes an existing call is particularly desirable.
The present invention is directed to methods and apparatus for providing call retry and/or call waiting services using AIN functionality including, e.g., AIN Monitor_For_Change functionality.
AIN Monitor_For_Change functionality allows a service control point (SCP) to request and obtain line status information from a telephone switch. In accordance with the present invention, an AIN based call retry service is provided using Monitor_For_Change functionality.
In one exemplary embodiment of the retry service, an AIN trigger, e.g., TAT trigger, is used to invoke SCP control when a call is received. The SCP instructs the telephone switch (SSP) at which the trigger was activated to try and complete the call to the called party and to notify the SCP of the results of the call completion attempt. If the call can not be completed because the called party""s line is busy, the switch notifies the SCP of the failure to complete the call due to a busy line condition.
In response to the information that the call was not completed due to a busy line condition, the SCP instructs the telephone switch to send the call to an intelligent peripheral device (IP) which plays the calling party a message and provides the calling party an opportunity to wait for the called party to complete the ongoing call or to leave a message for the called party.
Assuming the calling party decides to wait for the called party to complete the existing call, the IP will periodically signal the SCP to resume call processing. Each time the SCP resumes call processing it checks on the status of the called party""s line using the AIN monitor for change functionality.
If, in response to the line status check, the SCP receives status information indicating the called line is no longer busy, the SCP will instruct the switch to complete the call to the called party""s line, e.g., using AIN Offer_Call functionality. If the returned line status information indicates the called line is busy, the SCP will increment a call retry count. The call retry count is then checked to determine if it has reached a maximum value corresponding to the maximum amount of time a call party is allowed to wait before being transferred to voice mail.
If the retry count has not reached the maximum value the SCP has the call reconnected to the IP where the caller may again be given the opportunity to go to voice mail or continue to wait. Once a set amount of time at the IP has passed, the IP will signal to the SCP via the switch to resume call processing, e.g., to check on the line status again in an attempt to complete the call.
When the retry count has reached the maximum permitted value, the SCP will cause the call to be transferred to the called party""s voice mail. The transfer may be preceded by the IP playing the called party a message indicating that the called party is still busy on another call so they are being transferred to the called party""s voice mail.
The AIN based enhanced call waiting service of the present invention combines incoming call notification and called party call disposition selection features with the ability to hold an incoming call until an existing call is completed.
In accordance with one exemplary call waiting embodiment, incoming calls to enhanced call waiting service subscribers activate an AIN trigger at the terminating telephone switch which services the called party. In response to activation of the AIN trigger, an SCP is contacted by the switch for call processing instructions. If the SCP determines that the called party""s line is busy, the SCP initiates notification of the incoming call to the call waiting subscriber. The incoming call notification may be achieved using TAPI Display_Text functionality for subscriber""s which have a TAPI device, using talking call waiting speech notification capabilities supported by the telephone switch or by Internet notification via the transmission of an incoming call notification message to the call waiting service subscriber""s computer via the Internet.
In addition to being provided with the identity of the incoming caller, the called party is presented with the opportunity to indicate how they want the incoming call to be handled. The called party may indicate, e.g., by using a computer to send a message via the Internet, that they want to 1) take the incoming call; 2) have the caller wait; or 3) to send the call to voice mail. In the exemplary embodiment, the called party""s call disposition selection is communicated from the called party""s computer to an Internet customer access server which relays the disposition information to the SCP.
If the SCP receives information indicating that the called party wants to take the incoming call, the SSP is instructed to offer the call to the called party who can than accept it by putting the first call on hold by briefly depressing the switch hook. If, however, the SCP receives information indicating that the call is to be transferred to voice mail or fails to receive call disposition information from the called party, the SCP will cause the SSP to transfer the call to a voice mail system which services the called party.
If the SCP receives information indicating that the called party wants to have the calling party wait until the ongoing call is completed, the SCP sends the incoming call to an IP. The IP plays the calling party a message, e.g., indicating that the called party is on another call and has requested that the calling party wait until they finish the ongoing call. After a set interval of time, the IP signals the SCP to continue call processing. The SCP responds by sending a message to the SSP to check the status of the called line.
If the line status information returned by the SSP to the SCP indicates that the called line is no longer busy the SCP instructs the SSP to complete the call to the called line.
However, if the line status information returned by the SSP to the SCP indicates that the called line is still busy the SCP will increment a call retry count. The value of the call retry count, is then compared to a maximum retry count value. The maximum retry count value is indicative of a set maximum period of time a caller will be kept waiting before being sent to voice mail. If the call retry count has not reached the maximum value the call will be reconnected to the IP to wait for the set period of time. Once the set amount of time at the IP has passed, the IP signals to the SCP via the SSP to resume call processing, e.g., to check on the line status again in an attempt to complete the call.
When the retry count has reached the maximum permitted value, the SCP will cause the call to be transferred to the called party""s voice mail. The transfer may be preceded by the IP playing the called party a message indicating that the called party is still busy on another call so they are being transferred to the called party""s voice mail. As part of the call transfer operation, the SCP may instruct the SSP to notify the called party that the waiting caller has been transferred to voice mail. In the case of notification via the SSP, the notification may be in the form of a text message displayed using a TAPI device located at the called party""s location.
In the above described manner, the same functionality used to provide the call retry service of the invention is combined with incoming call notification, and the collection of call disposition information from a called party, to provide the enhanced call waiting service of the present invention.
The AIN based call retry service and the AIN enhanced call waiting service of the present invention can be offered in conjunction with other AIN and/or switch based services. For example, the services of the present invention can be combined with, and offered to, both switch based and AIN based Centrex service subscribers.
Accordingly, the call retry service and enhanced call waiting service of the present invention provide an opportunity for a telephone service provider to increase the number and/or types of services provided to customers.
Various additional features and advantages of the present invention will be apparent from the detailed description which follows.